Fuel feeding device



=1O the suction valve is open.

Patented Aug. 18, 1931 UNITED siATEs PATENT* OFFICE] p. WILLIAM A..EDWARDS,V F CHICAGO, ILLINOIS,` lSSIGrNOIlt T0l STEWARTWARNER-CORPORATION, OF CHICAGO, ILLINOIS, A; CORPORATION OF VIRGINIA FUELFEEDING; DEVICEy Application filedY October 23,1925). ASerial No.401,871.

The purpose of this invention `is to provide an improved fuel feedingdevice for supplying an internal combustion engine, particularly adaptedfor utilizingthe Vapor of the 5 fuel, which undercertain conditions isformed in the apparatus, for offsetting the variation of the fuelmixturel which sometimes results from air drawn vinto the intakemanifold fioin the vacuum chamber Ywhile The invention. consists in theelements and features of con- Y struction shown and described asindicated in the claims. i

In the drawings:

15 y Figure l is agdiagrammatic View showing a vacuum tank embodyingthis invention in its posit-ion on the vehicle' relative to the intakemanifold and carbureter.

Figure 2 is a vertical axial section of the fuel feeding deviceembodying the invention.

Figure 3 is avv detail section showing in side elevation the float stemconnection with the atmosphere valve stem.

-Referring to the drawings:

The engine intake manifold is indicated at X, the carbureter at Y, andthe vacuum tank in its entirety at Z.`

In detail the vacuum tank comprises the outer or `reserve fuel chamber,A, and the 0 inner'or vacuum chamber, B, the latter being telescopinglymounted vwithin the vupper partfof the reserve chamber, A, the detailconstruction for that purpose being that the reserve chamber A, isclosed at the top'by a cap member, A1, which is a metal stamping formedwith a flange, al, fitting outside the upper end of said chamber, A,said stamping being made to form-a cylindrical shoulder, a2, and saidcap having a central aperture, indicated at a3, for admitting the vacuumchamber, B, which is dimeiisioned for fitting said aperture, andlias anout- -turnediiange, b1, 'lapping the margin of the aperture, a3. Thechamber, B, is provided r with a cap, B1, having a down-turned marginalflange, B10, fitting outside the cylindrical shoulder, a2, of the capmember, A1, of the outer chamber. A packing gasket, Z9, is interposedbetween the flange, b1, andthe web ofthe-cap, B1, for renderingthe-vacuum manifold of the engine,

chamber fluid-tight. A gasket, b5, isalso shown interposed between saidflange, b1, and the inner marginal flangaw, of the cap, A1, butinasmuchas the outer chamber, A, necessarily has an atmosphere vent, shown at33, this" precaution is not` essential. The several parts mentionedarefsecured together by clampy screws, as, taking through the severallapped flanges and the intervening p gaskets."

For like reason, viz.,tliat the chamber has atmosphere vent, the cap,A1, need not be fitted airtight over the upper end of the chamber, butis made afairly snug fit to prevent to'oea'sy or accidentaldisplacement.

The' construction as thus far described it willbe understood facilitatesassembling and disasseinbling of the parts, since 'the inner vacuumchamber, B, may bev withdrawnl Without detaching the cap, and 'thereforewithout `necessity for releasing any of the clamp screws, we", since thecap, A1, may-be withdrawn from the chamber, A, with the chamber, B.` 4

In the horizontal web of the cap, B1, there is `mounted a fuelinletfitting, F, for connection with the fuel supplypipe, f, indicatedin Figure l as leading tothe main fuel tank at'the rear of the vehicle.end of the fitting, F, is furnished with' a strainer, F1, as seen inFigure 2.

' At the center 'of the horizontal web of the cap, B1, of the vacuumchamber, there is -mounted a fitting, E, arrangedfor connec- Y, tionwith the pipe, e, leading from a suction source indicated in Figure 1 asthe intake The fitting, E, has a restricted passage, 20, constitutingthe suction inlet. `For convenience of guiding the float stem, ashereinafter explained, there is secured rigidly to the inner end'dofthe'ftting, E, at-the inner end of the passage,20, a short tube,'25.This tube has nofunction in connection with the suction, advantage beingmerely taken of the presence of the duct, 20, for securing this guidetube to the The vinner n l fitting, E, a tube being employedinstead of arod, as necessary to avoid closing the inlet assage'. l l The fitting,E, iSbored from its inner end,

as seen at 26, to form the atmosphere valve chamber, and for aconnection, as hereinafter described, leading to the atmosphere space ofthe outer chamber, A. At the inner end of the bore, 26, there is mountedrigidly a tubular fitting, 27 whose duct constitutes the continuation ofthe atmosphere inlet, and which at its upper end affords seat for theatmosphere valve, 28, the latter having a stem, 31, extending downthrough and protruding Afrom the lower end of said fitting, where itobtains guidance in the latter, the atmosphere access to the chamberbeing mainly afforded by lateral ports, 29, 29, in the tting, 27, nearthe lower end of the fitting, E.

The connection mentioned from the atmosphere valve chamber to the airspace of the outer chamber, A, is afforded by-a pipe member, 30, havingone end connected to the upper end portion ofy the atmosphere valvechamber, 26, and the other end inserted through the cap, B1, and thelapping flanges, b4, of the vacuum chamber, and a4 of the cap, A1, ofthe outer chamber. The connection at this point is not necessarilyair-tight, but only suliiciently snug to prevent accidental displacementof the pipe, 30.

lVithin the vacuum chamber there is provided a float, 40, having a stem,41, arranged for operating the atmosphere valve for opening and closingat predetermined high and low levels of the liquid content of thechamber. Inqdetail, the construction for connecting the float stem withthe atmosphere valve and for` guiding the float, consists in forming thelower end ofthe atmosphere valve stem, which is bent transversely atitslower end, with an eye, 32, in which the slender stem, 41, ofthe ffloatmoves freely, the float stem being benttoform a stop shoulder, 41:?,near its lower end attachment to the float, and a second shoulder, Y41",at a distance above the `rst mentioned shoulder equalto thepredetermined range rof movement of the float between high and lowlevels, said-stem being bent in hook form at its upper end above the.last mentioned shoulder, as seen at 41, to provide a transverselyextending terminal,

41d, at a suflicient distance above the'shoul# der, 41", to permit theco-operation of said stem with the ttings, 27, and 25rigid with Vthelitting,`E, and which-are spaced apart, as

seen at .44, a distance suiicient to admit'the transverse terminal, 41d,of the float stem and allow it toslide easily between said two fittings.The transversely bent end of the atmosphere valve stem-it will beunderstood is dimensioned for putting the eye, 32, in alignment with thespace, 44, between said -two fittings.

From the foregoing descriptionit will be understoodthatthe float stem,.41, may be engaged with the eye, 32, so as to place the shoulder, .41",abovesaid eye, and the gagement of the upper end hook between the twofittings, 25, and 27; and that at the limit of the range of movement forwhich opportunity is thus afforded, the lower shoulder, 41a, willencounter the transverse terminal of the atmosphere valve stem at theeye, and open the valve. It has been demonstratedthat the suction holdon the atmosphere valve under ordinary running conditions of the engineserved by this apparatus, will operate to delay the opening of the valveuntil the lioat becomes submerged to an extent .for developing itsbuoyant value to a. degree which will open-the 4valve abruptly andfully, with theelect for which a snap action has been commonly provided;and accordingly, snap action is dispensed with in thepresent structure.

The operation of lthe structure above described may be understood fromthe descripi tion of the structure, but maybe further described asfollows: Starting with-the apparatus empty, and with the fuel supplytpipe connected with the maint-ank and the suction pipe connected withthe intake manifold of the engine, the float, 40, will holdtheatmosphere `valve securely seated, and the operation of the engine,developing vac- .uum in the vacuum chamber, will cause the yfuel to belifted from the main tank and discharge in the vacuum chamber, liftingthe float until the lower shoulder, 41a, of the float stem, encountersthe eye, 32, of the atmosphere valve stem, openingthe atmosphere valveand admitting atmospheric pressure from the outer chamber, B, which, as

mentioned, is at all times under atmospheric pressure by reason of theatmosphere vent 33. The access of atmosphere to-thefvacuum chamberafforded `by the ports, 29, .29, is

`designed to be so greatly in excessof the to permit the discharge ofthe liquid content of the vacuum chamber into v,the rcv.serve chamberwithout any embarrassing delay, and upon the lowering of the level ofthe liquid in the vacuum chamber to .predetermined degree, bringing vtheupperL shoulder, 41h, of the float stem into engagement with the eye,32, at ,the end of the atmosphere valve stem, the weight of the floatcloses the atmosphere valve, and the vG I1t`1,111 1,ous access ofsuction restores the condition of vacuum in the vacuum chamber, causingthe cycle of operation to be repeated.

An advantage over previous constructions of this general character whichis obtained by the construction described, is obtained by virtue of theprovision for admitting atmosphere to the4 vacuum chamber by Way of theouter fuel reserve chamber, instead of directly from the outeratmosphere, as in all previous constructions With which I am familiar.The atmosphere being thus taken from the outer chamber, comes to thevacuum chamber charged more or less with vapor of fuel Which is liableto be developed in the outer chamber by reason of the entire apparatusbeing exposed to engine heat due to mounting in the customary positionshown under the hood in front of the dash; and it thus results that inthe filling phase When engine suction is operating to produce vacuum inthe vacuum chamber, the fluid drawn to the intake `manifold is moreuniformly charged with fuel vapor than is the case When the atmosphereadmitted to the vacuum chamber in the emptying phase is derived from theouter air, and thereby is not charged With fuel vapor.

I claim:

1. A vacuum tank having a vacuum chamber and reserve chamber into whichthe vacuum chamber discharges, and; having a cover closing the vacuumchamber and the reserve chamber at the top, said cover having anexteriorly projecting member bored for a suction port, and counterbor'edfrom the outer end for pipe connection to the suction source, saidmember being bored from the under side of the cover laterally of thesuction port to form an atmosphere inlet valve chamber, and a tubularfitting secured in said member forming at its upper end a valve seat andprotruding down in the vacuum chamber, an atmosphere inlet controllingvalve seated at the upper end of said tubular fitting and having itsstem extending through said fitting, the member being laterally boredfor connection with the valve chamber of the first mentioned bore, thecover having an opening into the annular part of the reserve chamber,and a pipe connecting the lateral bore of the member With said lastmentioned opening.

2. An apparatus for lifting fuel for supplying an internal combustionengine comprising a vacuum chamber having a valvecontrolled atmosphereconnection and having also connection with a source of suction, and afuel reserve chamber having an atmosphere inlet and arranged toderivefuel supply from the vacuum chamber at intervals between periods duringwhich the vacuum chamber derives fuel supply by suction from the fuelsource; a duct opening in the upper part of the fuel reserve chamber ata point therein above the high liquid level of the vacuum chamber andleading therefrom into communication with the vacuum chamber and therebywith the suction source, the suction connection of the vacuum chamberWith the source of suction being continuously open; whereby vapor offuel which may accumulate in the upper part of the reserve chamber, andwhich in the emptying phase of the vacuum chamber may bedrawn from thereserve chamber past the open atmosphere valve into the vacuum chamber,is drawn through the vacuum chamber to the suction source.

3. An apparatus for lifting fuel for supplying an internal combustionengine comprising a vacuum chamber having a valvecontrolled atmosphereconnection and having also connection With a source of suction, and afuel reserve chamber having an atmosphere inlet and arranged to derivefuel supply from the vacuum chamber at intervals between periods duringwhich the vacuum chamber derives fuel supply by suction from the fuelsource; a duct opening in the fuel reserve chamber at a point thereinproximate to the level of the atmosphere inlet to said reserve chamberand leading therefrom into communication With the vacuum chamber at apoint above the high liquid level of the latter, the suction connectionof the vacuum chamber with a source of suction being continuously open.

In testimony whereof, I have hereunto set my hand at Chicago, Illinois,this 21st day of October, 1929.

WILLIAM A. EDVARDS.

